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Andrew Huberman and the Physiological Sigh

When it comes to understanding the dynamics of stress, few have delved deeper than the esteemed neuroscientist Dr. Andrew Huberman. The connection between breathing patterns and stress levels, in particular, has been an area of significant focus in his research.

The Challenge of Real-Time Stress Reduction

While many of us are familiar with the healing power of breathwork classes, meditation retreats, and wellness weekends, these methods, as magical as they might seem, have a fundamental flaw: they're not always practical in the real world. With the increasing demands of modern life pressing on us, there is a growing need for real-time stress solutions that don’t take us out of the moment.

Historical Discovery of the Physiological Sigh

It might surprise some to learn that the physiological sigh, a pattern of breathing associated with rapid stress reduction, was first discovered in the 1930s. This discovery was later expanded upon by experts like Professor Jack Feldman and Mark Krasnow.

The Science Behind the Physiological Sigh

This pattern is not just a quirk of human physiology. It's a natural response that even happens during our deepest sleep. When there's too much carbon dioxide building up in our bloodstream, this sigh - characterized by a double inhale followed by an extended exhale - naturally occurs. It involves not just the major parts of our lungs but millions of tiny air sacs. By optimizing the function of these sacs, we can more effectively remove excess carbon dioxide.

Practicing the Physiological Sigh

The physiological sigh is extremely straightfoward to practice and easily fits into ones daily life;

  1. Begin with a deep inhale through your nose
  2. Without exhaling, take a second, shorter inhale
  3. Exhale fully through your mouth, ensuring you empty your lungs.

By avoiding exhaling between the nose inhales, you can maximise the stress-relieveing benefits of this breathing technique.

Real-Life Observations and Practical Applications

This breathing pattern is not exclusive to humans. Anyone who's observed their pets might have noticed a similar pattern, especially as they relax or sleep. What’s empowering is that we can take conscious control of this naturally occurring pattern and use it to manage stress. The technique involves a simple double inhale, ideally through the nose, and a longer exhale.

The Relationship Between Breathing and Heart Rate Variability

Heart Rate Variability, or HRV, has become a buzzword in health and wellness circles. Yet, its relationship with breathing is often underexplored. Our breath, particularly the diaphragm's movement, plays a crucial role in modulating our heart rate.

Exhales vs. Inhales and Their Impact on Heart Rate

It’s simple: emphasizing exhales calms us down, and focusing on inhales energizes us. This phenomenon, rooted in the mechanical and neurological intricacies of our respiratory system, has profound implications for stress management. By controlling our breath, we can quite literally control our heart's response to stressors.


Understanding the physiological sigh is more than just a scientific curiosity. It’s a tool, accessible to all of us, ready to be harnessed for better stress management. By observing and practicing this breathing pattern, we can approach the challenges of life with a newfound sense of calm and control.

If you're eager to explore additional methods on not only reducing stress, but also enhancing sleep, have a look at our post on Yoga Nidra and the transformative benefits that come along with the ancient technique.

If you'd like to watch Andrew run through this in short, check out this great clip from the Tim Ferris Podcast

FAQ Section

1. What is the Physiological Sigh?

A physiological sigh is a breathing pattern involving two deep inhales through the nose followed by one long exhale. It's a natural part of the human physiology and occurs subconsciously, and if this pattern can be consciously controlled, it can be a great tool for managing stress in everyday life.

2. Is it Better to Breath Through your Nose or Mouth?

For the physiological sigh, it's beneficial to inhale through your nostrils as the filter out dust and other allergens in the air you're breathing in, allowing an increased amount of oxygen reaching your lungs. When exhaling in the physiological sigh, breathing out of the mouth is key to completely emptying your lungs.

3. How Many Times Should you do the Physiological Sigh?

Repeating the physiological sigh 1-3 times is sufficient to decrease stress levels in the moment, allowing you to feel more calm in the time of need.